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Retinal function and morphology in rabbit after intravitreal injection of VEGF inhibitors.

Cardiakidis Myers, Anna LU ; Lövestam Adrian, Monica LU ; Bruun, Anitha LU ; Ghosh, Fredrik LU ; Andréasson, Sten LU and Ponjavic, Vesna LU (2012) In Current Eye Research 37(5). p.399-407
Abstract
Purpose/Aim: To explore changes in morphology and function in the rabbit retina after intravitreal high-dose injection of three commonly used VEGF inhibitors.



Materials and methods: Forty-eight rabbits of mixed strain (6 months of age, body weight ≈ 3 kg) were randomized into four groups (n = 12). They were examined with full-field electroretinography (ERG) and with multifocal electroretinography (mf ERG) prior to drug exposure. The rabbits were then injected intravitreally with bevacizumab, ranibizumab, pegaptanib, or with a balanced saline solution. The dose of VEGF inhibitor was chosen to achieve a vitreous concentration approximately three times higher than the one clinically used in the adult human eye. ERG was... (More)
Purpose/Aim: To explore changes in morphology and function in the rabbit retina after intravitreal high-dose injection of three commonly used VEGF inhibitors.



Materials and methods: Forty-eight rabbits of mixed strain (6 months of age, body weight ≈ 3 kg) were randomized into four groups (n = 12). They were examined with full-field electroretinography (ERG) and with multifocal electroretinography (mf ERG) prior to drug exposure. The rabbits were then injected intravitreally with bevacizumab, ranibizumab, pegaptanib, or with a balanced saline solution. The dose of VEGF inhibitor was chosen to achieve a vitreous concentration approximately three times higher than the one clinically used in the adult human eye. ERG was then performed 8 weeks postinjection, and mf ERG 9 weeks postinjection. After 9 weeks, the rabbits were sacrificed and the sectioned retina was studied. Immunohistochemical analysis was performed of rods, cones, rod bipolar cells, horizontal cells, and amacrine cells.



Results: Rabbits injected with VEGF inhibitors all showed significantly lower amplitude of the dark-adapted b-wave rod-mediated response to dim light, compared to the rabbits injected with BSS. The a wave (reflecting photoreceptor function) in the response to single flash white light was however not affected. Immunohistochemistry revealed a significant reduction in PKC labeling of rod bipolar cells in pegaptanib and ranibizumab injected eyes whereas bevacizumab injected eyes displayed normal PKC labeling. No apparent morphological change was seen with markers for remaining retinal cells.



Conclusions: Our results indicate that the use of high-dose intravitreal VEGF inhibitors in the rabbit eye affects rod-mediated retinal function and PKC expression in rod bipolars cells for at least 9 weeks after drug administration. The three VEGF inhibitors influence the retina slightly differently. These results are important for the understanding of drug action and when devising therapeutical strategies in new areas such as retinopathy of prematurity where vitreous volume is significantly lower compared to the adult eye. (Less)
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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Current Eye Research
volume
37
issue
5
pages
399 - 407
publisher
Taylor & Francis
external identifiers
  • wos:000302914900008
  • pmid:22510009
  • scopus:84859906379
ISSN
0271-3683
DOI
10.3109/02713683.2011.611609
language
English
LU publication?
yes
id
0dbb9b4b-585e-401d-97d4-9146a093e66f (old id 2519330)
alternative location
http://www.ncbi.nlm.nih.gov/pubmed/22510009?dopt=Abstract
date added to LUP
2012-05-06 17:27:44
date last changed
2017-05-21 04:32:50
@article{0dbb9b4b-585e-401d-97d4-9146a093e66f,
  abstract     = {Purpose/Aim: To explore changes in morphology and function in the rabbit retina after intravitreal high-dose injection of three commonly used VEGF inhibitors. <br/><br>
<br/><br>
Materials and methods: Forty-eight rabbits of mixed strain (6 months of age, body weight ≈ 3 kg) were randomized into four groups (n = 12). They were examined with full-field electroretinography (ERG) and with multifocal electroretinography (mf ERG) prior to drug exposure. The rabbits were then injected intravitreally with bevacizumab, ranibizumab, pegaptanib, or with a balanced saline solution. The dose of VEGF inhibitor was chosen to achieve a vitreous concentration approximately three times higher than the one clinically used in the adult human eye. ERG was then performed 8 weeks postinjection, and mf ERG 9 weeks postinjection. After 9 weeks, the rabbits were sacrificed and the sectioned retina was studied. Immunohistochemical analysis was performed of rods, cones, rod bipolar cells, horizontal cells, and amacrine cells. <br/><br>
<br/><br>
Results: Rabbits injected with VEGF inhibitors all showed significantly lower amplitude of the dark-adapted b-wave rod-mediated response to dim light, compared to the rabbits injected with BSS. The a wave (reflecting photoreceptor function) in the response to single flash white light was however not affected. Immunohistochemistry revealed a significant reduction in PKC labeling of rod bipolar cells in pegaptanib and ranibizumab injected eyes whereas bevacizumab injected eyes displayed normal PKC labeling. No apparent morphological change was seen with markers for remaining retinal cells. <br/><br>
<br/><br>
Conclusions: Our results indicate that the use of high-dose intravitreal VEGF inhibitors in the rabbit eye affects rod-mediated retinal function and PKC expression in rod bipolars cells for at least 9 weeks after drug administration. The three VEGF inhibitors influence the retina slightly differently. These results are important for the understanding of drug action and when devising therapeutical strategies in new areas such as retinopathy of prematurity where vitreous volume is significantly lower compared to the adult eye.},
  author       = {Cardiakidis Myers, Anna and Lövestam Adrian, Monica and Bruun, Anitha and Ghosh, Fredrik and Andréasson, Sten and Ponjavic, Vesna},
  issn         = {0271-3683},
  language     = {eng},
  number       = {5},
  pages        = {399--407},
  publisher    = {Taylor & Francis},
  series       = {Current Eye Research},
  title        = {Retinal function and morphology in rabbit after intravitreal injection of VEGF inhibitors.},
  url          = {http://dx.doi.org/10.3109/02713683.2011.611609},
  volume       = {37},
  year         = {2012},
}